Pneumatic brake.



F. L GHAPSAL A. L. E. SMLLQTl` PNEUMATIC BRAKE. APPLICATION FLED FEB. 27,1914.

l fill IN YENTURS:

. WITNESSES CZd ZM f. MMM. z

FRANQOIS JULES CHAPSAL, OE PARIS, .AND ALFRED LOUIS EMILE SAILLO'I, 0F LA GARENNE-COLOMBES, FRANCE.

PNEUMATIC BRAKE.

Application led'February 27, 1914.

To all whom t may concern:

Be it known that we, FRANgois JULES CHAPSAL and ALFRED Louis EMILE SAiLLoT, citizens of the French Republic, residing at Paris, and La Garenne-Colombes, Department of the Seine, inFrance, have invented certain new and useful Improvements in or Relating to Pneumatic Brakes; and we do hereby declare the following to be a full, clear, and exact description ofthe invention, such as will enable others skilled in the art to which it appertains to make and j p "voir'so-called a re-filling reservoirjof a volume .as greatas desired, while the auxuse the same.

This invention relates to brake application accelerators of the kind described in the United States Patent, No. 929,551, dated July 27, 1909. These iinprovementsrelate to new means for controlling the charging and exhausting of the chambers and consist in 1. Combining the bra celerating valve of the lower chamber, with an automatic interrupter ofVrapid action constituted by a piston valve interposed between the distributer and the exhaust ori-. iice for the air of the train pipe, the slide valve and its facing renderingthis double acting accelerator applicable as a doublel acting distributer accelerator to compressed air brakes having an auxiliary reservoir, the,

regulating reservoir being replaced in this case by a .special air reservoir for refilling purposes having a volume as great as desired, while the auxiliary reservoir is connected directly with the upper chamber of the double acting accelerator converted into a distributing accelerator; the complete graduation during the application and release of the brakes with a proportional refilling of the auxiliary reservoir at each release being thus carried into effect, while the same apparatusmay be used as a double acting accelerator of a compressed air brake having a single chamber adapted to be graduated during the release and application of the brakes by closing with' aplugthe orifice of communication with the atmosphere and by leaving open to vthe-atmosphere the circular groove which'terminates at the brake cylinder, the regulating reservoir being then connected with the circular groove communicating with the main conduit through the medium of the piston of the antifluctuator, the

Specification of Letters Patent.

e i application acdistributer being connected- Patented J une 19, 1917.

seriai No. 821,375.

through the medium of a pipe opening into the upper chamber of the accelerator.

2. In modifying the distributer described in the specification of the British Patent of addition No. 4485/14 filed on the 20th Feb- 4ruary 1914, so as to control the automatic iliaryreservoiris connected directly with the upper 'chamber of the double acting accelerator y converted into a distributer. In the accompanying drawing Figure 1 illustrates a section through the modified double'actingacceleraton the antiiuctuator, the automatic Ainterrupter, the braking accelerating valve, the valve being in the central position of the movable membrane which controls them.

.l Fig. 2. shows the position occupied by this valve when the` movable membrane is raised at the end Qfl the stroke.

Fig. 3 illustrates the position of the same .valve corresponding to the complete lowering ofthe movable membrane.

The accelerator comprises two chambers I and S separated by themovable membrane M rwhich may be replaced by a piston. The main or train conduit opens at 1 into the accelerator and the air of this conduit passes On the one hand, through the `conduits 2 and 3 into the lower chamber I, raising thus the movable membrane M which brings the valve T to the end of its stroke into the position shown in Fig. 2.

On the other hand, through the channels 4 and 5 under the valve of the antifluctuator 6. If this air is supplied slowly under this valve, he spring R remains completely extended as illustratedin Fig. l1 and allows the train or main conduit air to pass above the valve 6, through the conduit 7 and the ports 8 and 9 whence it subsequently passes through the conduit 10 into the conduit 11 which through the medium of the circular conduit 12-12 brings it to the pipe R connected with the regulator reservoir. The air passing through the conduit 11, 12 also tinuous brake. It follows therefrom that when during the graduation of the braking during the descent of long inclined stretches of road, slight leakages take place in the main conduit, their only effect can be to produce a slight increase of the braking effort as the rapid action can not produce a fresh direct exhaust to the atmosphere of the air contained in the main conduit through the medium of the accelerating valve.

Release of the brakes.

If in order to release partially or completely the brakes, the main conduit is refilled, the valve 6 of the anti-fluctuator (see Fig. 1) remains, first of all, seated on its seat 141-14, as the pressure exerted on the upper face of this piston is equal to the pressure of theregulating reservoir which remains invariable during the application of the brakes. It follows therefrom that the flexible membrane M is raised and pushed to the end of its stroke (see Fig. 2) effecting, lirst of all, the closure of the valve 15 for accelerating the application of the brakes, then the opening` of the port 13 through which air from the controlling reservoir passes to the upper chamber S, and, therefore, to the branch leading to the distributer. The increase of pressure which is a consequence thereof produces, at a certain moment, the movement of the movable membrane and of the valve T in the opposite direction, this movementsto'pping when the lower edge of this valve closes again the port 13, the valve 15 remaining closed.

To each supply of air into the main conduit, a partial supply of air from the regulating reservoir corresponds therefore immediately in the upper chamber S and in the branch leading to the distributer, giving rise to an increase of pressure slightly superior to that of the main conduit until the pressure on both faces of the movable membrane are balanced. The refilling of the branch, and, therefore, the release of the brake, are graduated until the release of the brakes is complete corresponding to the moment when the controlling reservoir is completely expanded into the upper chamber and into the branch. The additional filling of the main conduit has, therefore, for its effect to replace the brake members into the operative position (see Fig. 2) as the operated movable membrane M is pushed to the end of its stroke.

We claim:

1. In an air-brake system for railway trains, the combination with the train pipe and an air reservoir, of an accelerator comprising a valve and means to open the same upon a reduction of pressure in the train pipe, and means to control the discharge of air from said valve to the atmosphere comprising a second valve, and a piston con` trolling the movement of said second valve, said piston being subject on one side during application of the brakes to the pressure of air in said reservoir and at the other side to the pressure of the air in the train pipe.

2. In an air-brake system for railway trains, the combination with the train pipe and an air reservoir, of an accelerator comprising a valve and means to open the same upon a reduction of pressure in the train pipe, means to control the discharge of air from said valve to the atmosphere compris ing a second valve, and a piston controlling the lmovement of said second valve, said piston being subject on one side during application of the brakes to the pressure of air in said reservoir and at the other side to the pressure of the air in the train pipe, means to supply air from the train pipe to said reservoir, and a valve to cut off communication between the train pipe and said reservoir when the pressure in the train pipe is reduced to a predetermined limit.

3. In an air-brake system for railway trains, the combination with the train pipe and an air reservoir, of an accelerator comprising a valve and means to open the same upon a reduction of pressure in the train pipe, a second valve also operated by said means, means to control the discharge of air from said first-named valve to the atmosphere comprising a third valve, and a piston controlling the movement of the same, said second valve serving to place one side of said piston in communication with said reservoir upon a `reduction of pressure in the train pipe and said piston being subject at its other side to the pressure of air in the train pipe.

In testimony whereof we affix our signatures, in presence o-f two witnesses.

FRANQOIS `IULES CHAPSAL. ALFRED LOUIS EMILE SAILLO'I.

Witnesses:

HANsoN C. Coxn, EMILE KLoTz.

Copies of this patent may be obtained for ve cents each, by addressing the Commissioner of Patents Washington, D. C. 

